To calculate the rate of interest, we use the equation:
![Interest\:paid=Amount\:borrowed* Rate\:of\:interest* Time](https://img.qammunity.org/2023/formulas/mathematics/college/2u1l2rpye0t8x590jf1ova3kotwl7ukci2.png)
Where we have
Interest paid = $53.97
Amount borrowed = $700
Time = 8 months = 8/12 (conversion factor: 1 year = 12 months)
Putting those values in the equation, we get:
![\begin{gathered} 53.97=700* Rate\:of\:interest*(8)/(12) \\ Rate\:of\:interest=0.11565=11.565\%\approx11.6\% \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/83hzdcwlih7azee7rnijykmc0nlj620938.png)
The rate of interest is 11.6%.